Electric heating system for buildings and structures



Jan. 23, 1951 J. L. MUSGRAVE ELECTRIC HEATING SYSTEM FOR BUILDINGS AND STRUCTURES Filed Dec. 4, 1946 Patented Jan. 23, 1951 ELECTRIC HEATING SYSTEM FOR BUILDINGS AND STRUCTURES Joseph Leslie Musgrave, London, England, as

signor, by mesne assignments, to Dulrae Limited, London, England, a-British company In Great Britain September20, 1944 3 Claims. (01. 219-19 I Application. December 4, 1946, Serial No. 714,016

This invention relates to electrical heating systems for the warming of buildings and structures, and in particular to that system known as Dulrae panel warming in which the electric elements are attached or secured to, the walls and ceilings of a structure or are used for any other purpose where it is desired to provide heat.

In the Dulrae system the conductor wires are laid and attached to a sheet or strip of insulating material which is laid'between, or on, sheets or strips of insulating material to which an adhesive substance is applied, before being passed through rollers. Or the Dulrae material is incorporated with, or secured with adhesive to, plaster boards or slabs, plywood, or other board, slab or sheet, or plastic or cemented material, so' that either the exposed surface of the board, slab, sheet or strip etc., or the exposed surface of the Dulrae material forms the surface from which the heat is transferred.

In the drawing:

Fig. 1 is a sectional view through a sheet or strip illustrating the application of a length of conductor wire thereto; and

Fig. 2 is a plane view of the length of Wire applied to the sheet of Fig. 1.

Now according to this invention instead of laying and attaching the conductor wires to a sheet of insulating material and securing this insulating material by an adhesive substance to the contiguous materials, I lay and attach the conductor wires 5 to an adhesive material in sheet or strip form 3, possessing insulating as well as adhesive properties, and lay the sheet or strip 3 of such adhesive material with the conductor Wires 6 attached thereto on or between insulating material (not shown), which may be placed between or on plaster boards, plywood or other boards, slabs, sheets, strips, plastic, cemented or other material. Where the plaster boards, plywood or other boards, slabs, sheets, strips, or plastic or cemented material possess suflicient dielectric strength the sheet or strip of adhesive material 3 carrying the conductor wires 6 may be laid directly between such boards, plywood, slabs, sheets, strips, plastic, cemented or other material.

Heat is then applied so as to render the sheet orstrip 3 of adhesive material to which the conjductor wires 6 are attached active adhesi-vely, which heat may be applied by passing the material with the contiguous materials through heated pressure rollers, or by placing them betweeiithe heated platens of a press, or the heat may be applied internally by passing current I sheet;

through the conductors before the material passes through the pressure rollers or while the material is being rolled, or before or while it is between the platens of the press.

As illustrated in the drawing, the conductor wire Gmay be further secured to the sheet 3 by means of tabs 4, 6, I, 8, struck from the sheet Fig. 2 illustrates the conductor wirefi as disposed in adjacent rectangular loops whose ends 6a are secured under vertically pivoted tabs 4 struck from the sheet and leaving subjacent openings 5.

The parallel portions of the rectangular loops of wire 6 are disposed under tabs 1 and 8 which are arranged alternately in series and are horizontally pivoted. For better securing of the wire 6 to the sheet 3, the tabs I extend in one "direction while the adjacent tabs 8 extend in the opposite direction.

What I claim as my invention and desire to secure by Letters Patent is:

1. An electrical heating panel comprising a relatively thick and at least somewhat flexible sheet of thermoplastic insulation material, said sheet adapted to be rendered adhesive when heated, tabs struck outwardly slightly from said adhesive sheet at one surface thereof, connected lengths of resistance wire of a cross-section up to that which does not materially exceed the thickness of said thermoplastic sheet, said lengths of resistance wire being laterally spaced from one another and each wire length being deeply embedded in said sheet and in the under surfaces of certain, of said tabs and sheet so that said wires are retained in place as a substantially integral part of said thermoplastic sheet and tabs, a plane-surfaced support for said thermoplastic sheet and adhered to the sheet by the latter, as the sole connection between the two, and a second sheet of insulation material covering said wires and adhered to the thermoplastic sheet by the adhesive characteristicsof the thermoplastic 2. The method ofproducing a three element, two layer electrical heating panel for room ceilings, walls, or the like, which comprises cutting a plurality of at least two spaced series of oppositely ldirected tabs in a thermoplastic sheet of insulation material which becomes adhesive when subjected to heat, training resistance wire in a predetermined path under said tabs on said sheet, heating the sheet of thermoplastic material to make some adhesive and compressing a stiffenipg slgeet against the wire-carrying surface of the sheet of thermoplastic material while the latter is hot, whereby to embed the resistance wire therein and in said tabs while adhering the stifiening' sheet thereto.

3. The r'nethod of producing a four element, three layer electrical heating panel for room ceilings, walls}; or the like, which comprises cutting a plurality of spaced series of oppositely directed tabs in a thermoplastic sheet of insulation material which becomes adhesive when subjected to heat, "training resistance wire in a predetermined path under said tabs on said sheet,,heat' ing the sheet of thermoplastic material to make same adhesive and simultaneously compressing stiffening, sheets of insulation material against opposite sides of said thermopiasticsheet whereby to embed the wire therein. and in said tabs whileadhering the stiffening sheets. thereto, the said thermoplastic sheet being hot when said operation: is performed.

JOSEPH LESLIE MUSGRAVE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

